Filament cutoff and holding head

ABSTRACT

In a rod-wrapping machine moving a filament supply about a rod to be wrapped, an improved filament cutoff and holding head is provided with an L-shaped slidably mounted grab which is moved by a double acting air cylinder to extend under a final turn of the wrapping and then be retracted to cutoff the filament against a knife edge and clamp the filament adjacent to the knife edge. The head has a filament positioner which pushes the clamped filament away from the head at the start of a winding cycle. A diaphragm overrides the double acting cylinder to slightly move the grab and release the filament.

'2 Unite States Ptet [is] 3,641,859

Bishop et al. Feb, 15, 1972 [54] FILAMENT CUTOFF AND HOLDING 3,448,5066/1969 Bishop et al. ..29/202.5 X

HEAD

Primary Examiner-James M. Meister [72] Inventors: John M. Bishop,Orange; Emmett F. A"0mey J Bradley cohn Simon, Garden Grove, both ofCalif,

[73] Assignee: The Conolon Corporation [57] ABSTRACT 22 i Man 2 1970 Ina rod-wrapping machine moving a filament supply about a rod to bewrapped, an improved filament cutofi and holding [21] Appli727 head isprovided with an L-shaped slidably mounted grab which is moved by adouble acting air cylinder to extend under 521 U.S. Cl ..83/566, 83/701,83/902, final turn of the pp and be retracted to cutoff the 83/909 242/719 filament against a knife edge and clamp the filament adjacent [51]Im. Cl ..B23d 31/00 to the knife g The head has a filament positionerwhich [58] Field of Search ..242/7. 1 9; 29/2025, 240, 208 R, Pu h s theclamped filament away from the head at the start of 29/452; 83/566, 701,902, 909 a winding cycle. A diaphragm overrides the double actingcylinder to slightly move the grab and release the filament. [56]References Cited 4 Claims, 9 Drawing Figures UNITED STATES PATENTS2,640,653 6/1953 Wodetzky ..242/7.19

PNENTEBFEB 15 1972 3,641,859

L INVENTORS: o JOHN M. BISHOP 37p 7 4| BY EMMETT F. SIMON 3542i ATTORNEYFILAMENT CUTOFF AND HOLDING HEAD BACKGROUND OF THE INVENTION In our US.Pat. No. 3,448,506, a yarn or filament cutoffand holding head is shownin FIGS. 27-30 and in FIGS. 22-25 designated by the numeral 196. Thecutoff and holding head shown in this patent did not provide windings ofthe high quality desired as it allowed overwraps of the turns at thestart of the winding cycle. This invention provides an improved filamentcutoff and holding head which provides superior rod wrappings.

SUMMARY OF THE INVENTION A filament cutoff and holding head has a bodywith a flat front end from which a slidably mounted downward extendingL-shaped filament grab extends. A cutoff knife is mounted adjacent tothe grab and projects beyond the front end of the body. Opposite theknife above the grab there is slidably mounted a filament positionerhaving a forward facing notch disposed over the edge of the grab.

On winding a rod, a final turn of a filament is laid in the extendedgrab which is retracted to clamp the filament and cut it off against theknife. At the start of a subsequent wind, the positioner is slid forwardto align the first winding after which it is retracted and the grabreleases the filament. The grab remains retracted during the entirewinding to allow the filament to clear its end until the final turn atwhich time the grab is again extended to receive the filament and againclamp and cut it.

The filament positioner is activated by a rocker arm and a single actingair cylinder with a spring return. The grab is activated by a rocker armwhich connects a double acting air cylinder to it. The double acting aircylinder moves the grab from an extended to a closed cutting andclamping position. To release the clamped filament, a diaphragm islocated at one end of the double acting air cylinder to override it andslightly move the grab.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view ofafilament cutoff and holding head according to this invention;

FIG 2 is a rear view of the head fixed to a mounting bracket with tworocker arms mounted thereon;

FIGS. 3 and 4 are sections taken on lines 3-3 and 44 of FIG. 2 showingthe air cylinders which activate the head; and

FIGS. 5 through 9 are side views of a fragment of a rod and a fragmentofthe front ofa head showing stages in the winding ofa filament about arod according to this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 1, the filamentcutoff and holding head 10 has a body 11 fixed to a mounting flange 12.Body 11 has a flat front surface 13. Slidably disposed on a longitudinalstep in the top of body 11 is the filament grab 15 which has a long flatcentral shank 16 and an L-shaped downward extending grab 17 at its frontend. The rear end of grab 15 has a longitudinal downward extendingflange 18. A cutoff knife 19 is fixed by screws 20 and 21 to the side ofbody 11 and has the forwardly extending substantially vertical knifeedge 22 formed thereon adjacent to the outer edge of grab 17. An upperhorizontal flange 23 of knife 19 slidably secures grab 15 to body 11. Afilament positioner 24 is centered over the inner edge of grab 15adjacent to flange 23. Positioner 24 rests on a higher step 25 of body 11 and extends into a channel 26 formed in the longitudinal raised side27 of body 11. The rear end of positioner 24 has a vertical,longitudinal flange 28 formed on it and the front end of positioner 24has a V-shaped notch 29 formed in it.

As shown in FIG. 2, head 10 is mounted on a bracket 30 which is fixed toa winding head as described in our aboveidentified patent. Rocker arms31 and 32 are mounted in the central pivots 33 and 34. By means ofarticulated clamps 35 and 36 the arms are connected to the piston rods37 and 38 of pneumatic cylinders.

Referring to FIG. 4, a single acting cylinder 39 has an air inlet 40 tomove its piston 41 against a return spring 42. Thus activation ofcylinder 39 extends the filament positioner 24 by means of arm 32.

Referring to FIG. 3, a double acting air cylinder 45 contains a piston46 and the air inlets 47 and 48. Introduction of air into inlet 48extends grab l5 and into inlet 47 retracts it. A diaphragm 50 behind thelarger area end 51 of cylinder 45 has a stop 52 on it so that, when airis introduced through inlet 53, it forces piston 46 to the left as shownto override and move grab 15 a short distance and release a filament aswill be described.

Referring now to FIGS. 5 through 9, this invention operates in thefollowing manner. At the start of a winding cycle, as shown in FIG. 5,air is introduced into inlet 47 of FIG. 3 to cause grab 15 to holdfilament 60 against the flat front face 13 of body 11. A rod 61 ispositioned to be wound. As winding head 62 moves behind and around rod61 as shown in FIG. 6, filament positioner 24 is extended by activatingcylinder 39 of FIG. 4. Positioner 24 catches filament 60 in notch 29 toextend it as shown to allow the first turn of the winding to be startedtrue and in line with the plane of rotation of head 62. While the firstwinding is being completed, cylinder 39 is deactivated to allow spring42 to retract the filament positioner 24. At about the same time, air isintroduced momentarily into inlet 53 of FIG. 3 to cause diaphragm 50 tomove against piston 46 to move it a short distance to the left as shownto cause grab 15 to release filament 60.

Winding continues as shown in FIG. 7 until. as shown in FIG. 8, grab 15is fully extended by introducing air into inlet 48 of FIG. 3. Thisallows the final winding to be laid in grab 15 which is then retractedto cut off and clamp filament 60 as shown in FIG. 9. Filament 60 is cutoff as it is forced against knife edge 22 by grab l5 and the cut end offilament 60 is clamped between grab 15 and the flat front end 13 of body11 as shown in FIG. 5 where the front end of knife 19 is broken away.Knife 19 may be longitudinally positioned by screws 20 and 21 so thatfilament 60 will be simultaneously cut and clamped. This inventionproduces neater and more precise rod wrappings 64.

What is claimed is:

1. In a rod-wrapping machine having a filament supply about a rod to bewrapped with a winding of filament, an improved filament cutoff andholding head comprising, in combination, a body having a front face, aslidably mounted L- shaped grab on said body extending in front of saidflat face, a knife edge fixed on said body adjacent to one side of saidgrab extending in front of said flat face, a filament positionerslidably mounted on said body over the side of said grab opposite saidknife edge, means extending said grab to have a final wind of saidfilament wound therein and retracting said grab to cut off said filamenton said knife edge and clamp the filament between the L-shaped grab andsaid flat face of said body, means extending said filament positioner topush said clamped filament forward at the start of a winding, and meansmomentarily extending said grab releasing said filament after the startof a winding.

2. The combination according to claim 1 wherein said means extendingsaid filament positioner is a single acting pneumatic cylinder having aspring return and wherein said means extending and retracting said grabis a double acting air cylinder.

3. The combination according to claim 2 wherein said means momentarilyextending said grab to release said filament is a diaphragm of largerarea than said double acting cylinder at one end thereof overriding saiddouble acting cylinder.

4. The combination according to claim 3 with the addition of a bracketand two rocker arms, said body being mounted at one end of said bracket,said pneumatic cylinders being mounted on the other end of said bracket,one of said rocker arms connecting said single acting cylinder to saidfilament positioner and the other of said rocker arms connecting saiddouble acting cylinder to said grab.

1. In a rod-wrapping machine having a filament supply about a rod to bewrapped with a winding of filament, an improved filament cutoff andholding head comprising, in combination, a body having a front face, aslidably mounted L-shaped grab on said body extending in front of saidflat face, a knife edge fixed on said body adjacent to one side of saidgrab extending in front of said flat face, a filament positionerslidably mounted on said body over the side of said grab opposite saidknife edge, means extending said grab to have a final wind of saidfilament wound therein and retracting said grab to cut off said filamenton said knife edge and clamp the filament between the L-shaped grab andsaid flat face of said body, means extending said filament positioner topush said clamped filament forward at the start of a winding, and meansmomentarily extending said grab releasing said filament after the startof a winding.
 2. The combination according to claim 1 wherein said meansextending said filament positioner is a single acting pneumatic cylinderhaving a spring return and wherein said means extending and retractingsaid grab is a double acting air cylinder.
 3. The combination accordingto claim 2 wherein said means momentarily extending said grab to releasesaid filament is a diaphragm of larger area than said double actingcylinder at one end thereof overriding said double acting cylinder. 4.The combination according to claim 3 with the addition of a bracket andtwo rocker arms, said body being mounted at one end of said bracket,said pneumatic cylinders being mounted on the other end of said bracket,one of said rocker arms connecting said single acting cylinder to saidfilament positioner and the other of said rocker arms connecting saiddouble acting cylinder to said grab.